[1] Seoul Natl Univ, Coll Med, Spine Ctr, 166 Gumiro, Songnam 463707, South Korea
[2] Seoul Natl Univ, Coll Med, Dept Orthopaed Surg, Songnam 463707, South Korea
[3] Seoul Natl Univ, Bundang Hosp, Songnam 463707, South Korea
[4] Columbia Univ, Med Ctr, Dept Orthopaed Surg, New York, NY USA
[5] New York Presbyterian Hosp, New York, NY USA
[6] Kangwon Natl Univ Hosp, Dept Orthopaed Surg, Chunchon, South Korea
[7] Armed Forces Yangju Hosp, Dept Orthopaed Surg, Yangju, South Korea
[8] Seoul Natl Univ, Coll Med, Dept Orthopaed Surg, Seoul, South Korea
[9] Seoul Natl Univ Hosp, Seoul 110744, South Korea